And just this month, Dick Van Patten’s Natural Balance finalized a merger with Del Monte.

So, why is this a problem?

To put it simply, with mass production, quality always suffers. (Compare boxed macaroni and cheese with the dish made at home from scratch.) At the same time, the bigger a company becomes, the harder it is for those at the helm to control quality. Then there’s economic pressure: When I’ve invested millions of dollars, I need to see a return on my investment … and that can lead to dangerous practices like taking shortcuts and substituting inferior materials because they’re cheaper.

That’s exactly what’s happened with pet foods. The pressure to turn out the most products at the lowest cost has led to some disturbing developments in the pet food industry — something you’d never know by looking at the pictures of glowing, healthy animals on the front of dog food packages. The truth is that many inexpensive commercial foods contain questionable and sometimes unwholesome ingredients, including animal byproducts from rendering plants — items such as beaks, feet, bones, eyes, intestines, brains and even offal — and large amounts of grain and starchy vegetables that provide cheap filler calories.

Setting aside the “yuck” factor of animal byproducts, let’s look for a moment at those grains and veggies. Since they’re a dominant ingredient in many dry dog foods, they must be beneficial, right? Well, not exactly. In fact, dogs don’t need carbohydrates. Scientists tell us that when dogs were wolves, their carbohydrate consumption was around 14 percent. Today, however, many commercial dry dog foods have carbohydrate levels closer to 75 percent. Why? Because carbs are plentiful, stable, and cheap — not because they’re especially nutritious.

We can’t talk about dog food ingredients without also mentioning the ever-increasing incidence of dog food recalls that have sickened and killed thousands of pets.

Take the cases of Doane Pet Care, Diamond Pet Foods and Menu Foods, the three major companies that produce food for many private label and brand name dog foods. In the last 15 years, foods manufactured by these three mega-companies have killed well more than 4,000 dogs from contamination with a variety of deadly toxins, including 2007’s most lethal pet food contamination in history. That year, thousands of dogs suffered acute liver failure after consuming food produced by Menu Foods and sold under brands such as Iams, Eukanuba, Science Diet and Mighty Dog. Some 3,400 dogs died before the problem was traced to Chinese wheat gluten and rice protein concentrate contaminated with melamine, a chemical used in plastics and fertilizers, which had been added to increase the protein content.

But dog food recalls have hit independent manufacturers, as well, under brand names like Nature’s Recipe, Royal Canin, Innova, and just this year, Natura, Nutri-Vet and Milo’s Kitchen.

So what’s a dog owner to do?

The best thing is to stay educated. Consider subscribing to email recall notices from the FDA and nonsponsored sites like Dog Food Advisor. (Simply do a web search for “dog food recalls.”) Publications such as Whole Dog Journal and Bark and organizations like the Humane Society are also great sources of information. You’ll also learn who owns what in the pet food business, which can make you a more careful consumer and a more responsible caretaker of your companion.

Next month, I’ll take a look at choosing food, feeding guidelines and supplements.

Joan Merriam lives in Nevada County with her Golden Retriever Casey (hence, “Casey’s Corner”). You can reach Joan at joan@joanmerriam.com. And if you’re looking for a Golden, be sure to check out Homeward Bound Golden Retriever Rescue.